Muscle, tendon, and nerve changes after botulinum toxin injections for post-stroke spastic equinovarus
Exploratory, Longitudinal Study to Define Changes in Muscle, Tendon and Neural Properties After Botuline Neurotoxin Type A (BoNT) Treatment of Spastic Equinovarus in First-ever Stroke Patients: a Pilot Study.
This pilot will use 3D ultrasound and instrumented spasticity tests to see how botulinum toxin injections change muscle, tendon, and nerve properties in adults with post-stroke spastic equinovarus.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 12 (estimated) |
| Ages | 40 Years to 60 Years |
| Sex | All |
| Sponsor | Universitaire Ziekenhuizen KU Leuven Academic / other |
| Locations | 1 site (Leuven) |
| Trial ID | NCT06767631 on ClinicalTrials.gov |
What this trial studies
This is an open-label, non-randomized pilot with four visits spanning baseline, injection, early follow-up, and a later end-of-study visit timed to the known action of botulinum toxin. At each visit investigators will perform three-dimensional freehand ultrasound (3DfUS) and instrumented spasticity assessment (ISA) on the medial gastrocnemius and tibialis anterior of both legs to measure muscle, tendon, and neural properties. The design captures pretreatment, peak effect, and later-stage changes to inform sample size calculations and refine measurement methods for a future observational study. The goal is to generate quantitative data that could help optimize injection timing, dosing, and longer-term management strategies.
Who should consider this trial
Good fit: Adults (≥18) with first-ever unilateral stroke who have pes equinovarus due to spasticity and a clinical plan for botulinum toxin injection into the relevant lower-leg muscles are ideal candidates.
Not a fit: People without spastic equinovarus, not scheduled for botulinum toxin treatment, with bilateral or non-first-ever stroke, or with exclusionary musculoskeletal or neurological conditions are unlikely to benefit from participating.
Why it matters
Potential benefit: If successful, the methods could help doctors tailor botulinum toxin treatments to reduce harmful muscle changes and improve long-term function for people with spastic equinovarus.
How similar studies have performed: The 3DfUS and ISA techniques are recently developed and have limited prior use in this exact setting, so this pilot is largely exploratory rather than building on a large body of confirmed clinical results.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Voluntary written informed consent of the participant or their legally authorized representative has been obtained prior to any screening procedures * 2\. At least 18 years of age at the time of signing the Informed Consent Form (ICF) * 3\. Use of highly effective methods of birth control; defined as those that, alone or in combination, result in low failure rate (i.e., less than 1% per year) when used consistently and correctly; such as implants, injectables, combined oral contraceptives, some IUDs, true sexual abstinence (i.e. refraining from heterosexual intercourse during the entire period of risk associated with the Trial treatment(s)) or commitment to a vasectomised partner. * 4\. Pes equinovarus due to spasticity * 5\. Clinical need for BoNT injection at the lower leg * 6\. Any previous injection of BoNT into the muscles to be investigated was at least 3 months ago * 7\. First-ever, unilateral stroke Exclusion Criteria: * Musculoskeletal or other neurological problems affecting the lower limb * Presence of spinal cord pathology that could lead to spasticity, ataxia, dystonia * Cognitive problems that impede measurements * Severe co-morbidities * Irritated skin or open wounds where ultrasound will be placed * Pregnancy * Profound atrophy of the muscles in the target area(s) of injection * Participation in an interventional Trial with an investigational medicinal product (IMP) or device * The effect of botulinum toxin A can theoretically be potentiated by agents affecting neuromuscular transmission, such as aminoglycoside antibiotics (e.g., gentamicin, tobramycin), lithium salts, cholinesterase inhibitors and tubocurarine-like muscle relaxants ((cis)atracurium, rocuronium, suxamethonium, vecuronium). Therefore, patients on whom these medications are started during the course of the trail will be excluded.
Where this trial is running
Leuven
- Uz Leuven — Leuven, Belgium (Recruiting)
Study contacts
- Principal investigator: Fabienne Schillebeeckx, MD — UZ Leuven campus Pellenberg, secretariaat fysische geneeskunde en revalidatie blok 5
- Study coordinator: Fabienne Schillebeeckx, MD, PI
- Email: fabienne.schillebeeckx@uzleuven.be
- Phone: 0032 - 16338714
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.